The present invention relates to an organic field-effect transistor. Organic field-effect transistors known at the present time comprise: source and drain electrodes; a semiconductor layer made of an organic semiconductor material placed at least between said source and drain electrodes; a gate electrode; and an electrical insulator layer interposed between the gate electrode and the semiconductor layer.
When a potential is applied to the gate electrode, the charge carriers present in the semiconductor layer concentrate at the interface between the semiconductor layer and the insulator, while remaining only in the semiconductor layer. This concentration of charge carriers then forms the conduction channel characteristic of the on-state of the transistor.
Organic field-effect transistors are produced using organic semiconductor materials and are also known by the acronym OFET (Organic Field Effect Transistor).
An organic semiconductor is an organic compound, in the form of a crystal or a polymer, which exhibits properties similar to inorganic semiconductors. These properties are conduction by electrons and holes, and the presence of a bandgap. These materials give rise to organic electronics.
In particular, the discovery in 1970 of polymers having a conducting character has instigated a real surge in activity in the huge field of microelectronics, offering new prospects in the fabrication of components on low-cost plastic substrates. In the last few years, considerable progress has been made in this new field of research, commonly referred to as “plastic electronics”. Display screens based on organic light-emitting diodes (OLEDs) integrated into digital cameras, car radios or even in electric razors have already been commercialized. This fantastic development in OLEDs has therefore spurred research in other applications of organic electronics, such as photovoltaic solar panels based on organic semiconductors or organic field-effect transistors, which would allow the fabrication of low-cost integrated circuits on flexible substrates.
However, it is endeavored to improve the electrical conduction performance of organic transistors.